Somatosensory System Flashcards
What are the 3 types of somatosensory systems
Cutaneous (skin) sensation
Visceral (internal organs)
Proprioception (identity of limbs)
Which receptors in somatosensory system convert stimuli eg light into AP
Sensory receptors
What is a stimuli converted to in first step of sensory transduction
Receptor / graded potential
What happens if receptor/ grades potential reaches threshold due to large stimulus
AP can be fired
In AP initiation what suggests large stimulus
AP frequency
On the skin, what are the 2 layers called
Top epidermis and bottom dermis
Where are most receptors in skin found
In dermis (superficial)
What are the 4 skin receptors which are superficial
Merkels disk
Meissner corpuscle
Hair follicle receptor
Free nerve (no receptor)
What are the 2 types or deep receptors
Pacinian corpuscle
Ruffini’s corpuscle
What are the 3 nerve fibres connected to skin receptors
AB - large and myelinated (fastest)
A delta - small and myelinated
C - small and unmyelinated (slowest)
What is a receptive field
Area which a stimulus activates receptors and the nerve fibres
Which 2 receptors have small receptive fields
Meissner corpuscle and merkels disk
Which skin receptor detects stroking in a direction (large RF)
Ruffinis
What are slow adaptation receptors
Receptors which have a receptor potential and therefore fire AP all the way through a stimulus
What are fast adapting receptors
Receptors which have receptor potential / AP firing at start and end of stimulus not during
What are fast adapting receptors useful for
Identifying change Eg the slipping of an object